First of all, preparing for placements is a continuous process. You should never make this mistake to pile up things for the last moment. You should start preparing by brushing up your existing knowledge from the initial days only. In the final month of placement, you should only revise the concepts both basics and advanced. Here are some of the resources that you can follow for your preparation.
You can go through two websites, i.e. GeeksforGeeks and Glassdoor to learn about interview experiences.